/***** BEGIN LICENSE BLOCK *****
 * Version: EPL 1.0/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Eclipse Public
 * License Version 1.0 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy of
 * the License at http://www.eclipse.org/legal/epl-v10.html
 *
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 * Copyright (C) 2001-2011 The JRuby Community (and contribs)
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
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package org.jruby.util.log;

import java.lang.reflect.Constructor;
import org.jruby.util.cli.Options;

public class LoggerFactory {

    private static final String LOGGER_CLASS = Options.LOGGER_CLASS.load();
    private static final String BACKUP_LOGGER_CLASS = "org.jruby.util.log.StandardErrorLogger";

    private static final Constructor<?> CTOR;
    private static final Logger LOG;
    
    static {
        Constructor<?> ctor;
        Logger log;
        
        try {
            final Class<?> cls = Class.forName(LOGGER_CLASS);
            ctor = cls.getDeclaredConstructor(String.class);
            log = (Logger)ctor.newInstance("LoggerFactory");
        } catch (Exception e1) {
            try {
                final Class<?> cls = Class.forName(BACKUP_LOGGER_CLASS);
                ctor = cls.getDeclaredConstructor(String.class);
                log = (Logger)ctor.newInstance("LoggerFactory");
                
                log.debug("failed to create logger \"" + LOGGER_CLASS + "\", using \"" + BACKUP_LOGGER_CLASS + "\"");
            } catch (Exception e2) {
                throw new IllegalStateException("unable to instantiate any logger", e1);
            }
        }
        CTOR = ctor;
        LOG = log;
    }

    public static Logger getLogger(String loggerName) {
        try {
            Logger logger = (Logger) CTOR.newInstance(loggerName);
            return logger;
        } catch (Exception e) {
          Throwable rootCause = e;

          // Unwrap reflection exception wrappers
          while (rootCause.getCause() != null) {
            rootCause = rootCause.getCause();
          }

          if (rootCause instanceof SecurityException) {
            return new StandardErrorLogger(loggerName);
          }

          throw new IllegalStateException("unable to instantiate logger", e);
        }
    }
}
